[curiosity]

I don't see how the doctrine of mongenism would be compromised if Adam and Eve's descendants interbread with subhuman homonids, who we know co-existed with our species for tens of thousands of years.

As far as I can see, this is the only way to reconcile mongenism with the genetic evidence.

[Aquinasfan]

I don't see how the doctrine of mongenism would be compromised if Adam and Eve's descendants interbread with subhuman homonids, who we know co-existed with our species for tens of thousands of years.

Do we know this? With what degree of probability?

If interbreeding was possible, then the species would be human, wouldn't it? Where would these humans have come from if not from the original pair? If they didn't come from the original pair, would they have suffered the effects of original sin?

As far as I can see, this is the only way to reconcile mongenism with the genetic evidence.

I would question the evidence for subhuman hominids and/or their breeding with humans.